Two days after his return to the U.S., Warmbier's fever spiked, and his health continued to deteriorate. He died four days later.

"Now, we see North Korea claiming to be a victim, and that the world is picking on them and we're here to tell you North Korea is not a victim," said Fred Warmbier. "They're terrorists. They kidnapped Otto. They tortured him. They intentionally injured him."

Otto Warmbier was in the country with a China-based travel company called Young Pioneer Tours. He delivered a tearful, televised confession in March 2016, saying that he was bribed by a church member in Wyoming to steal the banner as a "trophy."